Baldwin's Ohio Revised Code (on Westlaw) and Page's Ohio Revised Code have annotated copies of the Ohio Constitution.
The current constitution in Ohio was originally passed in 1851, but has been amended numerous times since.
Contain summaries of relevant cases under each section of the Ohio Constitution, as well as cites to secondary sources.
The Northwest Ordinance was the governing document before Ohio became a state. The first Ohio constitution was the Ohio Constitution of 1802, which was replaced by the Ohio Constitution of 1851. The text of the various amended versions of the Ohio Constitution can be found on Westlaw. An 1874 constitution was created, but was not approved by the voters.
Ohio has had four constitutional conventions: 1802, 1850-51, 1873-74 and 1912 (links are to brief descriptions of the conventions). The first two resulted in new constitutions. The new constitution created in the 1873-74 convention was rejected by voters. The 1912 constitutional convention resulted in 42 proposed amendment, 34 of which were approved by voters.
The links below are transcripts of the convention proceedings, which can be used as "legislative history" materials for interpreting the Ohio Constitution.
Photo: 1912 Ohio Constitutional Convention, by Ohio History Central.